Draft and lift mechanism for potato diggers



Sept. 25, 1951 L. E. SMITH- 2,569,201

DRAFT AND LIFT MECHANISM FOR POTATO DIGGERS FledNov. 7, 194e 5 sheets-sheet 1 MN. Nw mw Nw WN QN mw Sept. 25, 1951 l.. E. SMITH 2,569,201

DRAFT AND LIFT MECHANISM FOR POTATO DIGGERS Filed Nav. 7, 194e 5 sheets-sheet 2 Sept. 25, 1951 l.. E. sMlTH 2,559,201

DRAFT AND LIFT MECHANISM FOR POTATO DIGGERS Filed Nov. 7, 1946 5 Shee'cs--Sheefl 5 Sept. 25, 1951 E. SMITH DRAFT AND LIFT MECHANISM FOR PoTATo DIGGERS 5 Sheets-Sheet 4 Filed NOV. 7, 1946 Sept. 25, 1951 L E, sMlTH 2,569,201

DRAFT AND LIFT MECHANISM FOR POTATO DIGGERS Filed NOV. 7, 1946 5 Sheets-Sheet 5 Patented Sept. 25, 1951 DRAFT AND LIFT MECHANISM FOR POTATO DIGGERS Lewis E. Smith, Congress Park, Ill., assigner to International Harvester Company, a corporation of New Jersey Application November 7, 1946, Serial No. 708,229

10 Claims. (Cl. 55-9) This invention relates to a potato digger. More specifically, it relates to an improved construction for moving a power driven potato digger to and from a ground digging position.

The type of potato digger or harvester with which the presentinvention is concerned is generally connected to and drawn behind a mobile power unit such as a tractor. The digger is provided with a frame supported on ground wheels and has at its forward end a digging shovel. A shaker conveyor is generally mounted for longitudinal movement on the frame and is connected by means of a driving mechanism to the power take-01T of a tractor.

During the operation of the digger, it becomes 4desirable to raise and lower the digger shovel either for the purpose of depth adjustment or to .lift the same into a transport position. A lifting unit, such as a hydraulic system on the tractor., may be utilized for accomplishing this purpose.

Considerable power effort on part ofthe tractor is generally necessary to move a digger of this type. The ldigger may be worked under :hard fground conditions and the weight of the machine thus makes it necessary for the tractor to exert considera-ble draft power. For the same reasons, the lifting means employed v-is also required to exert a great deal `of force in moving the digger shovel out vof the ground digging Ypesi-tion.

The type Iof lifting linkage employed between the tractor and the vdigger has in ythe past generally been of such construction that the lifting force utilized :had to assume the ydraft `power ,i

during `the lifting operation. In order to accomplish lifting of the -digger shovel, it has Abeen common in mostrconstrnctions to employ aljack knife type or toggle lconstruction :connected :be-

tween :the tractor draw-bar andthe draftstruc- Xture of the implement. Then by -femploying -a vlifting cylinder in conjunction with the toggle linkage, lifting of the digger `shovel vis accomplished. It xis of courseobvious .in a `jack--knife -or ltoggle linkage Ldraft construction that there are two points of connection, one at the drawbarand `'one at :the -implement to bezraised. The ilifting 'force .-is generally `connected near the piv- 'otal connection of the links and in .making this V.point the two pointsof connection :are brought tractor is decreased as the digger is drawn toward the tractor by virtue of the lifting cylinder and the action of the toggle or jack-knife linkage.

From this fact, therefore, it is obvious that the power means, or lifting cylinder employed, must in addition to its lifting action assume the draft force which thetractor exerts in moving the digger forwardly. This is true geometrically in a toggle, jack-knife or parallel linkage construction.

As has been indicated the force required to break the implement from the ground is exceptionally great, andtherefore it is especially undesirable to require the lifting means to perform additional work. In all the previous constructions, however., the lifting mechanism had to assume certain draft forces since the action of the lifting linkage employed would draw the implement closer to the tractor during lifting.

It is the prime object of this invention, therefore, to provide an improved means for controlling the working depth of an agricultural implement and for lifting the same from -a ground working to a transport position.

It is another object to provide an improved lifting linkage for a tractor drawn implement, said linkage .being `constructed and arranged to raise and lower said implement from the ground while maintaining the Anormal longitudinal draft .distance .between the tractor and the implement.

.construction including a novel linkage arrangement -whereby the digging portion of the implement -may be raised whilemaintaining the draft .distance between the implement andthe tractor.

It is still another object kto `provide an yproved lifting linkage fora tractor-drawn potato digger, Asaid lifting vlinkage being operable to ling .the working depth of a .tractor drawnpotato 4digger, said linkage vincluding non-parallel vlinks operable to raise ,the potato ,digger shovel .Without substantial .forward movement of vthe .digger with respect to the tractor.

It is a further object rto provide an improved -caster wheel .construction for a ,tractor drawn .potato digger.

It is `a still further Lobject to provide an improved construction for simultaneously raising the adjustable discharge end of a potato digger upon the raising of the digger shovel or nose from a ground working position.

It is still another object to provide an improved drive construction for a potato digger, said drive construction includingha telescoping shaft which is in operative connection with a gear box mounted on the adjustable discharge end of the potato digger, said gear box being pivotally mounted whereby upon raising and lowering of the discharge end a substantially straight line of driving connection will be maintained through the telescoping drive. n

It is another object to provide an improved drive connection between a tractor and a tractor drawn potato digger.

Other objects and features of the present invention will become apparent from a reading of vthe following specification when examined in convtion of an improved liftinglinkage after the diggerv shovel has been lifted from the ground;

Fig. 3 is a sectional plan view of a portion of a tractor drawn potato digger taken along the line 3-3 of Fig. 2;

Fig. 4 is a fragmentary sectional view taken along the line 4-4 of Fig. 3;

Fig. 5 is a sectional view of a portion of a telescoping drive for a potato digger taken along the line 5-5 of Fig. 1;

Fig. 6 is a sectional view of a rear portion of a tractor drawn potato digger, said view being taken on linefS-Bof Fig. 1; v .A Fig. 7 is a side elevational view of a modified form of a tractor drawn potato digger in a ground engaging position;

Fig. 8 is a side elevational view of the same in a transport position;

Fig. 9' is a side elevational view similar to Fig. 2, this View, however, having portions of the structure removed to show detail parts of the lifting linkage for adjusting the potato digger shovel;

and

Fig. 10 is a plan view taken substantially along the line IU-Ill of Fig. 9 showing portions of the lifting linkage for adjusting the working depth of the potato digger shovel.

Referring particularly to Figs. 1, 2, 3 and 4, the rear portion of a mobile power unit, such as a tractor, is generally designated by the 4reference character I0. The tractor consists of a body portion II carried by an axle structure I2 to which are connected rear` ground wheels I3, only one of which is shown. A draw-bar structure I4 is connected to the axle structure I2. A power take-olf shaft I5 projectsV rearwardly from the body I I, the forward end of the shaft being suitably connected to the power source of the tractor (not shown). An operators station I6 is positioned on the rear of the tractorY I0.

. A potato digger designated generally by the reference character 20 is pivotally connected to the draw-bar structure I4 and is adapted to be drawn by and behind the tractor I0. For the .purpose ofthe present disclosure a one row type cludes a frame 2l carried by a transverse axle 22 pivotally mounted on ground wheels 23. The frame 2l includes a pair of downwardly extending spaced angle members 24. The angle members 24 provide a guide and support for the endless shaker conveyor 25 which is carried on a plurality of idler wheels 26 mounted on various positions on the frame 2|. A digging or ground engaging shove1 2l is positioned at the foremost portion of the frame 2 I.

An adjustable discharge section 28 is provided at the rear of the frame 2|. The discharge section 28 comprises a pair of spaced downwardly extending angle members 29 which are pivotally connected to the rear portion of the frame 2| as indicated by the reference character 30. A vertical bail element 3l is connected to the angle member 29.

The rear portion of the discharge section Z8 supports a transverse shaft 32 on which is mounted a pair of driven sprockets 33 (only one of which is shown), which drive the endless conveyor 25. A drive sprocket 33' is driven by drive chain 34 which in turn is driven by the sprocket 35. The drive sprocket 33 is effective to drive the endless conveyor 25. The sprocket 35 is keyed to a power output shaft 35' which is driven by means of gearing (not shown) within the gear box 35, said gear box best being shown in Fig. 6. The gear box 36 is mounted for pivotal movement between a vertical member 31 and a vertically extending arm of the bail member 3 I.

As best shown in Fig. 1, .a power input stub shaft 38 projects forwardly out of the gear box 36 and is connected by means of a universal joint 39 to a pair of telescoping members 4U, the foremost one of which is also provided with a universal joint 4I. The universal joint 4I is in operative connection with a short shaft 42 pivotally connected by means of a bearing 42 to a bracket 43. The short shaft 42 is in driving connection with a universal linkage 44 which is connected to the power take-01T shaft I5 of the tractor IIJ. As best shown in Figs. l and 2, a pair of telescoping shields 40 are provided to cover the telescoping shafts 4D. The rear shield 40' is connected, as best shown in Fig. 5, to a pair of channels 4I' which are connected at their rearmost ends to a portion of the gear box 36, as indicated at 42. The foremost shield 40 is similarly connected to a pair of channels 43 which have their forward ends connected to a bracket 44 connected to the bracket 43. The shields 40 and channels 4 I and 43 are in telescoping relation and serve to support the telescoping members 40.

The bracket 43 is rigidly connected to one of a pair of upwardly and forwardly extending spaced supports 45, which are connected to the angle members 24. The supports 45 form the main draft frame 46 of the potato digger. As best shown in Figs. 3 and 10, the forward ends of the supports 45 are rigidly secured to an angle 41 bent into the shape of a U. A channel or longitudinally extending lifting member 48 with the legs pointing downwardly is rigidly fastened to the angle 41, and at its rearward end, as indicated in Figs. 4 and l0, is connected to a brace structure 49. The brace structure 49 is further connected to a transversely extending support 50 by means of a bracket 5I. It can thus be seen that a rigid frame structure is provided that will absorb the stress loads developed in lifting the potato digger from its ground working position.

A box-type draft beam 52 is positioned beneath the supports 45 and frame 46 and extends forwardlylwith respectY thereto. k'I'lieboxf- .type .draft beam 52 is movablewith respect Vto the supports and frame 46`and by means of non-parallel links 53 and 54.` As best shown lin Figs. land 2, the rear links 54 are shorter than links 53 and are pivotally connected to the chan-V 4nelmember 48.` The forward links 53 are longer ,than the links 54 and are pivotally connected to a member 55 rigid with the supports 45 and the channel member 48.

It is of prime importance to note thedifferf ence in the length of the links 53 andl54 which by. virtue of` their construction movably'connect .theboX-type draft beam'52 and the channel or longitudinally extending lifting member 48 Vof =the frame 46`,in non-parallel relation... Thisnorrof the member 56 is-pivotally Vconnected to the draw-bar structure 4, as indicated at` 58.

vA Uv-shaped member 59, mounted on the for- V ward end of the box-type draft beam 52, pivotally' supports a casterl wheel structure 60. v The ,caster wheel structure60 comprisesa yoke 6| having downwardly extending arms 62r which support and permit pivotal or casteringV movement of the caster wheels 63. The yoke 6| is mounted for teetering `movement by means of a bearing 64 which is journalled on a pin 64 carried by the U-shaped member 59. i u Connected to each of the` supports 45 and projecting forwardly'thereof isa bracket 65. Each bracket 65 Apivo'tally4 supports 'a pair of links" 66, 'as best'shown in Figs.`2 and 3; The links 66'a`re pivotally connected to a rectangular structure .61 which comprises side members `68fand a 'U'' shaped bracket 69`which vstraddle's'and` rests upon the draft member 56. The links 66 andthe structure 61i'n effect form a togglelinkage; An L- shaped angle 'I0 is connected to eachside member 68 and functions to form a cradle for retaining the caster'wheel structure against pivotal movement when the caster wheels and the digger are raised as shown in Fig. 2.

A hydraulic lifting cylinder or fluid actuated extensible means 1| is connected to a triangular frame '|2- which is rigidly connected to the supports 45.v The piston rod 1| of the cylinder 1| is connected at its free end toand between a hand'side of the digger.

pair of spaced brackets 13 which in turn are rigidlyfastened to a pair of vertical lifting links 14 spacedly and pivotally connected at their lower ends to the box-type beam 52. The member 55 projects between thelinks 'I4 and actsas a` guide when lifting movement takes place, as will become more apparentfrom lthe operation.

The upper ends of the `lifting links 14 are pivotally connected to a pair of spaced triangular plate members 15 which are pivoted as at 16 be- .threads into a .tubular member 8 3 which is connectedto alink 84. Thelink 84;is'pivoted bef tween the triangular plates |5 as'indicated at '16 and is adapted to engage a'pin 85 transversely extending through the plates 'I5v for' imparting adjusting movement thereto. l "Asbest shown inFigs. 2 and 3, a bail member 86 is connected to the triangular plates 15.` The bail member 86v has connectedA thereto a 1ink`81 having a lostl motion vloop 88. A transversepin 89 extends through the loop 88 and is connected to a pairjof vertical members 90 best shown in Fig.3,wwhich are keyed to a transverse shaft 9| pivotallymounted in the supports 45. At vveach end"r0f the shaft 9| is keyed a vertical element 92 which in turn is connected to a pair `of longitudinal links 93 which, as shown in Fig. l, extend rearwardly and are connected to the ad justabl'e discharge end of the digger. l A vertical support 94 is mounted on the left- 'I'he support 94 mounts a manualadjusting means 95 for independently raising and lowering the adjustable discharge end ofthe digger. `The manualadjusting means l95 includes a'crank-arm 96 journalled in a. bearing 91. vThe; lower end of the crank-arm96is in threaded connection with a link 98 having a lostrmotio'n slot 99.' A pin |00 rides in the slot and isf'connected to anarm |0|, which is keyed to theshaft 9|. The digger shown in Figs. 7 and 8 shows a. modification in thedraft and lifting connection between the digger and the tractor. Similar parts are indicated by the same'reference characters. In the potato digger shown in Figs; 7 and `8, Ithe caster wheel structure is not utilized and is replaced by a roller truck member. generally `indicated by the reference character, |02. TheY truck v||l2.includes alongitudinal U-shaped frame or draw-bar extension, |03 which is piv- Otally attached as at |04 to a vertical bail member |05. The vertical bail member isfrigidly` attached to the draftbeam 52. A hitch connec# tion |06 suitably connects the `frame |03 to the drawbar o f` thertractor. A roller wheel |0'l is journalled on a `shaft |08 extending transversely through the legs of the bail Ymember |05. A pair "of gussets |09m(only one` of which is shown) rigidly Seeure the legs o f the 'bail member 4|05 to thebeam' 52. The brackets 65 of the modication shown in Figs. "1. and 8 each have connected thereto a member to which'is pivotally connected a link 'I'he link is in turn pivotally. and centrally connected to toggle links H2 and ||3. Toggle link 3 is pivotally connected to toggle link ||2 and to each leg of the U-shaped frame r| |13.'V TheV toggle link |2 is provided with pins or stops I4 which limit forward travel of the links when liftingV the diggen'as will be presently described.

Operation l Asbest shown in Fig. ,1, the potato digger 24,0 is drawn along Aby the tractor 0 with the shovel 21 digging into the ground. The sprocket 35 is driven by means 'of the gear box and the tele,- scopingu members '40' which in turn are 4driven from the power take-off shaft of the tractor. The chain 34'actuates the sprocket 33 whichgin turn Vdrives theshaker conveyor 25. After ,the potatoes `have been dug, the conveyor 25 shakes off the excess soil and carries them tothe ad- `,instable discharge: section 28, whereupon the po- Aebestfsnow iii, Figsi; 2 and 3,' theeaster Wheels .regulate the depth of .the digger shovel 21...,'1'he casterwheels'` .ride in the. furrowsat eachside of the ridg'eand by virtue f the center oscillating or teetering';.connection are free/.to oscillate when encountering uneven ground, thereby providing .smooth andeven. digging acf tion by ,the digger. Thev .downward thrust .967 casioned by the digging is .upon the .caster Wheels. .Ras'ing' andlowering of the digger. shovel may be .accomplished with ease by. the operator from hisgstationonthe tractor.4 When. the operator desires to raise' the potatc')A .digger shovel from the ground or to adjust the-.same he. c an .do ,so by meansof a hydraulic. lifting arrangement mounted on.th`e, tractor. The type. of lifting ar.- riigement whienimay be utilized is shwnin the patent tov C. W. `Mott 2,324,866, datedJuly y20,..19t3. Fluid is .supplied .from a4 hydraulic pump .(notshown) .mounted on .the tractor-.to a

conduit II5 which is in communication' with the hydraulic cylinder .1 I The piston rod 1I'. .thereupon'lpresses downwardly upon the spaced brackets 13`thereby exerting a downward. thrustv upon the lifting links 14. The doWnwai-'dithruston thelifting link 'Mforces the box .beam 52` downwardly' againstthe. caster wheel structure., ,Coli-..- tinuedehydraiilic action causes the noni-parallel linksY 53 and 54 to raise the longitudinally extending lifting member .which is' connected to the ,supports 45 and .thus raise the digger shovel. The d ownward..thrust,` therefore, ofthe lifting link 14, .is `initially `taken upon .the .caster Wheel structure 60. Thus as` the hydraulic pressure iricreases, the supports, 45and lifting member 48 pivot about the pivotal points of the non-parallel linksy 53 vand 54; and the supports thereupon are urgedupwardly causing the shovel pointA ofthe digger to, break from the ground. 4It is' of prime importance .to note at this point that .the caster wheelsabsorbthe initial thrustiof the' load ,oclcasionedby .the breaking of .the .digger Shovel fromthe ground... As. the distance between` the bfox beam .52' and the" lifting'v member. 48 v is'` inf creased` due .to .the continued. hydraulic action, the. supports' .45 .and their rigid structurelconf tinue .tol raise. and the links 66. therebyarealso pulled'up'wardly. The toggle arrangement of the links 66 and structure 61 causes lifting of the rectangular. structure. `I'l. and causes .the side memberss and the L-shaped angles to move upwardly` until they come in contact' and1 cradle the transversely extending portionoyf kthe yokelt, Ity can be` seen that the caster wheels are now rigidly cradled and vall teetering actionv ceases. The forward portion of the rectangular struc'- ture 61 is at all times bearing upon the upper surface of the draft member or draw-bar extension 56 and by virtue of a roller |03 is free tol roll on the upper fiat surface of said draft member 56. As the rectangular structure 61 cradles and engages thezyoke 6| on the caster wheel structure, lthe ycaster wheelv structure. is raised from the ground. y Asbest `seen in Fig'. f2, the point of. thrust is new no longer uponthe caster wheel on the ground but is'upon thejmemf ber56 and' `the drawbar I'4 of the rtractr'. '1l'he caster wheel is effective to absorb. theextreme and'severe load occasioned in breaking the shovel from the ground. As the shovel is free from" the ground, however,A theload is thereupon'shifted tothe member 56 byvirtue of the'linkage ar; 'rangement .of the rectangulanstructre. 6.1., .It should' be especially noted; .as being. of.' prime portance, that the digger shovel raised sub'- 8' mz stafritiallyvertically from the ground and by `.viitue ofthe vnon-,parallel links 53 .and 54 between ,theY box beam 52 and lifting member 48 the {lig} ger is not moved substantially closer to the traer. tor upon lifting. Since the tip of the digger shovel rotatesin aslight arc, the radius pointof which is on the axleof, the wheel 23, .therev is a slight movement of the tip'of the shovel closer tothe tractor, but this movement is negligible, Thereg fore the hydraulic, mechanism utilized is required onlytolift the digger from the ground andlis not requiredv to assume or overcomedraftforces which :would .be. occasioned by .a jack-knifev tog; gie link, or. parallel. link construction. view ofthe non-parallel link construction between the box b.eam. 52, .th`e-` longitudinal liftingv member mand the.supports.45l, movement between said members. is both, longitudinal,andvertical. theA potatopdigger is yraised from. the ground, the non-parallel linkage affords vertical .movement without, necessitating a decrease in thelongtudinal distance. between the axis of the wheelsof the' tractor .and .the wheels of the .potatov.ldigger. Stated inanother manner, the non-parallel link;- age construction .is'eiiective to providemove'f ment of thebox beam 52forwardly during lifting. Therefore, this movement .compensates for any fore-shortening of the distance between the digger andtthe tractor which would ordinarily result in lifting. Thus the .lifting means is not requiredto assume heavy draft forces. As the potato digger is raised from the Sposi?- tion shownin Fig. 1. to the position shownin Eig. 2V, thelifting links 14 operate to rotate the plates 15 in a counter-clockwise direction about their pivotal point 16. on the bracket. 1l. ...The counter-clockwise rotation actuates the link 8,6 to move forwardly thereupon causing the link 81 to engage the transverse pin 89 and thereby mov,- ing the vertical members 90 forwardly. This will rotate the shaft 9|, thereby causing forward movement rof the links 93 which are attached-to the adjustable discharge section 28. The discharge section 28 thereupon pivots at its pivotal point .30 :in .alcounter-clockwise manner, thus raising the rearmost end of the discharge section to the position indicated by phantom lines in Fig.. 1. The section must, of course, be raised to this position to permit raising of the digger shovel.

When the operator wishes to utilize the hydraulic' control for gauging the depth working position of the digger shovel 21, the discharge section 28 is thus also automatically adjusted. D u'ring' this operation, the shaker conveyor iS'. of our'se, in operationv and the .drive mechanism thereforvis functioning. It is extremely desir? able `tlie'refore that the telescopingI members 46 remain in'a Asubstantial straight line drive pohsitloiilwith respectv to the gear box 36, thus as s'uring e'fiici'entfdriving motion. Since the gear box 43,6y is pivotall'y 4mounted between the downwardlyextending leg of the bail. element 3l `and the vertical member l31, this straight line driving action is laccomplished since the gear box is free to rotate despitev any angular movement of the' discharge section 28 about its pivotal point 3,6. Stated in anothermanner, despite the height adjustment of .thed'ischarge section 28, the tele.- soping members .40,l remain in asubstantial longitlidinal straight line idrive byvirtue of the pivf otal connectionbetween the gear box and the discharge section.

' The shields 4U' `rel'also in telescoping'fengage-E- g. ment and rigidity of the telescoping members 4D is accomplished by virtue of channels 4l and 43 which are also in telescopic engagement.

The potato digger 20 may also be raised or the depth may be adjusted by means of the manual Wheel 82. Rotation of the wheel 82 causes upward movement of the link 84 until it engages the transverse pin 85 extending through the plate 15. Continued upward movement of the link 84 rotates the plate 15 in a counterclockwise direction, thereby urging the lifting links 14 .downwardly in the same manner as is accomplished by the hydraulic cylinder 1I. This, of course, raises and lowers the discharge section 28 in the same manner as .previously described.

`The position of the lost motion loop B8 with respect to the pin .89 determines at what point the discharge section 28 is to be raised upon raising of the potato digger shovel 2l. The crank arm 96 can vbe utilized to regulate the position of the discharge section 28 and may also be used for independently lifting said discharge rear section with respect to the digger shovel of the potato digger.

In the modification shown in Figs. 7 and 8, the lifting action of the draft beam .52 with respect to the supports 45 is the same as above stated. Downward pressure by the piston rod 1l forces the beam 52 and the supports l5 away from one another, the non-parallel linkage operating to raise the digger shovel in a substantially vertical line. The initial load in breaking the digger from the ground is taken by the wheel |01. Continued raising movement of the supports and the digger shovel causes opening of the toggle links H2 and H3 until the stops H4, as best shown in Fig. 8, limit further opening of said links. At this point vthe links are effective to lift the wheel lill from the ground and the lifting load is thereupon taken in the U-shaped frame |03 and the tractor drawbar I4.

It is now apparent that a unique lifting and adjusting structure for gauging and cutting the digging depth and raising the potato digger shovel has been accomplished. By virtue of this construction the potato digger shovel is raised in a substantially vertical direction Without the necessity of simultaneously drawing the implement closer tothe tractor. Thus, in effect, the lifting means employed is required to exert only a lifting pressure and is not required to assume draft loads during operation.

In view of the Vnovel ,caster means employed, the vpotato digger implement is provided with a maximum amount of maneuverability despite varying ground contour conditions. By virtue of the single and central pivotal connection of the caster wheel and yoke, ease in turning is also facilitated. Upon lifting, the greatest load encountered in breaking the digger shovel from the ground is also initially taken and assumed bythe caster Wheel structure.

As has been clearly set forth, an eflicient and practical means has been provided to simultaneously raise and lower a discharge section of the potato digger and in view of the unique universal drive construction, in conjunction with the manner of mounting the main gear drive box, a maximum and efficient drive is established .during al1 the positions the adjustable discharge section may take during the operation of the implement.

It is to be understood that additional changes and modifications may be made without departing from the spirit of the invention as disclosed and as defined in the appended claims.

Whatis claimedis:

1. For a trailing implement having a longitudinally :extending 'frame pivotally -supported on ground wheels, and `a ground engaging means connected at one end to the frame and pivotally movable with the frame with respect to the ground; alifting mechanism adapted to be connected to the longitudinally extending frame and to the :draw-'baro'f atractor comprising, a draft frame adapted to Ybe connected to the implement frame, said draft frame including a longitudinally extending lifting member, a longitudinally extending draft beam disposed below the lifting member, a, link pivotally connected to said draft beam .and to vsaid lifting member, a relatively longer 'second lin-k pivotally connected to said draft beamand tosaid lifting j'member, said links being ,positioned Vin relative non-parallel relation, means adapted to pivotally connect the draft beam to the draw-bar of a tractor, and, adjust-` ing. means connected between the .draft beam .and the longitudinal lifting member whereby the beam and the lifting member may be relatively moved apart thereby raising said draft frame whereby an implement lframe connected to said draft frame may also be raised.

,2. Fora trailing implement having a longitudinally extending frame :pivotally supported on ground wheels, and Va ground engaging means connected atone end to the Vframe and Vpivotally movable .with the iframe with respect to the ground; a lifting mechanism adapted to be connected to thelongitudinally.extending frame and to 'the draw-'bar cfa .tractor comprising, a f draft frame adapted to .bejnoniiected` to-,theimplement frame, said draft frame including a longitudinally extending lifting member,alongitudinally ,extending Ydraft vvbeam .disposed belowV the lifting member, .a short linkpivotally `connectedto the draft beam .and .to thelifting member, .a relatively longer link pivotally connected tothe draft beam and to the lifting member .forwardly `of the short-.link Yand in angular relation withrespect thereto whereby said llinks arepositioned in V-non-.parallel relation, means adapted `to pivotally'rconn'ect -the 'draft beam to the draw-bar of -a tractor, 'said means `including a draw-.bar extension pivotallyconnected to the draft beam, and a fluid iextensible'means connected .between the `draft beam -and the liftingmember whereby uponextension of thev extensible means said draft beam and lifting member are moved -ap'artthereby raising the draft frame whereby vanimplement frame connected to said draft framemay-also be raised `without substantially changing the longitudinal spacing between a tractor and the axle of the implementframe.

3. For `a `trailing implement having a longitudinallyextending lframe pivotally supported'on ground wheels, land a ,ground-engaging shovel connected at one "end ofthe frame and'pivotally movable 'with the frame with respect to the ground; a lifting mechanism. adapted to be connected to 'the longitudinally"extending frameand to the vdraw-bar of a tractor comprising, a draft frame adapted to be connected tothe implement frame, said draft frameincluding a longitudinally extending'li'fting member, a longitudinally extending draft -beam positioned `below the lifting member, non-parallel links pivotally connected tothe `draft beam-and .-to the lifting mechanism, a castering wheel 'structure connected to the draft beam for supporting the same, means pivotally connected to the draft beam, said means being adapted to connect said draft beam to the drawbar of a tractor, yand a fluid extensible means connected between the draft beam and the lifting member for moving said member and the beam relatively apart whereby the draft frame and an implement frame adapted to be connected thereto are raised without substantially changing the longitudinal spacing between a tractor and the axle of the implement frame.

4. For a trailing implement having a longitudinally extending frame pivotally supported on ground wheels, and a ground engaging shovel connected at one end of the frame and pivotally movable with the frame with respect to the ground; a lifting mechanism adapted to be connected to the longitudinally extending frame and to the draw-bar of a tractor comprising, a draft frame adapted to be connected to the implement frame, said draft frame including a longitudinally extending lifting member, a longitudinally extending draft beam positioned below the lifting member, non-parallel links pivotally connected to the draft beam and to the lifting mechanism, a wheel structure connected to the draft beam for supporting the same, means pivotally connected to the draft beam, said means including a draw-bar extension adapted to connect said draft beam to the draw-bar of a tractor, and a fluid extensible means connected between the draft beam :and the lifting member for moving said member and the beam relatively apart whereby the draft frame and an implement frame adapted to be connected thereto are raised Without substantially changing the longitudinal spacing between a tractor and the axle of the implement frame.

5. For :a trailing implement having a longitudinally extending frame pivotally supported on ground wheels, and a ground engaging shovel connected at one end of the frame and pivotally movable with the frame with respect to the ground; a lifting mechanism adapted to be connected to the longitudinally extending frame and to the draw-bar of a tractor comprising, a draft frame adapted to be connected to the implement frame, said draft frame including a longitudinally extending lifting member, a longitudinally extending draft beam positioned below the lifting member, non-parallel links pivotally connected to the draft beam and to the lifting mechanism, a wheel structure connected to the draft beam for supporting the same, means pivotally connected to the draft beam, said means including a draw-bar extension adapted to connect said draft beam to the draw-bar of a tractor, a iiuid extensible means connected between the draft beam and the lifting member for moving said member and the beam relatively apart whereby the draft frame and an implement frame adapted t be connected thereto are raised without substantially changing the longitudinal spacing between a tractor and the axle of the implement frame, and a lost-motion connection between said draft frame and said castering wheel structure whereby the castering wheel structure is raised upon the lifting of said draft frame to a predetermined height.

6. For a trailing implement having a longitudinally extending frame pivotally supported on ground wheels, and a ground engaging shovel connected at one end of the frame and pivotally movable with the frame with respect to the ground; a lifting mechanism adapted to be connected to the longitudinally extending frame and to the draw-bar of a tractor comprising. a draft frame adapted to be connected to the implement frame, said draft frame including a longitudinally extending lifting member, a longitudinally extending draft beam positioned below the lifting member, non-parallel links pivotally connected to the draft beam and to the lifting mechanism, a wheel structure connected to the draft beam for supporting the same, means pivotally connected to the draft beam, said means including a draw-bar extension adapted to connect said draft beam to the draw-bar of a tractor, a fluid extensible means connected between the draft beam and the lifting member for moving said member and the beam relatively apart whereby the draft frame and an implement frame adapted to be connected thereto are raised without substantially changing the longitudinal spacing between a tractor and the axle of the implement frame, and a toggle linkage construction including one link pivotally connected to said draft frame and a second link pivotally connected to the draw-bar extension, said toggle linkage construction being adapted to engage and raise said castering wheel construction upon the lifting of said draft frame to a predetermined height.

7. For a trailing implement having a longitudinally extending frame pivotally supported on ground wheels and a ground engaging shovel connected at one end cf the frame and movable with the frame with respect to the ground; a lifting mechanism adapted to be connected to the longitudinally extending frame and to the drawbar of a tractor comprising, a draft frame including a longitudinally extending lifting member, a longitudinally extending draft beam positioned below the lifting member, non-parallel links pivotally connected to the draft beam and to the lifting member, a castering wheel structure including a yoke extending transversely of the draft beam and pivotally connected thereto, castering wheels pivotally connected to the yoke in transversely spaced relation and adapted to support the draft beam with respect to the ground, a draw-bar extension pivotally connected to the draft beam and adapted to connect to the draw-bar of a tractor, and adjustable means connected to the draft beam and to the lifting member for moving the beam and the member relatively apart thereby initially raising the lifting member with the draft beam supported on said castering wheel structure.

8. For a trailing implement having a longitudinally extending frame pivotally supported on ground wheels and a ground engaging shovel connected at one end of the frame and movable with thek frame with respect to the ground; a lifting mechanism adapted to be connected to the longitudinally extending frame and to the draw-bar of a tractor comprising, a draft frame including a longitudinally extending lifting member, a longitudinally extending draft beam positioned below the lifting member, non-parallel links pivotally connected to the draft beam and to the lifting member, a castering wheel structure including a yoke extending transversely of the draft beam and pivotally connected thereto, castering wheels pivotally connected to the yoke in transversely spaced relation and adapted to support the draft beam with respect to the ground, a draw-bar extension pivotally connected to the draft beam and adapted to connect to the draw-bar of a tractor, adjustable means connected to the draft beam and to the lifting member for moving the beam and the 13 member relatively apart therebyv initially raising the lifting member with the draft beam supported on said castering wheel structure, and a toggle linkage construction including one link pivotally connected to said draft frame and a second link pivotally connected to the draw-bar extension, said to-ggle linkage construction being adapted to engage and raise said castering Wheel construction upon the lifting of said draft frame to a predetermined height.

9. For a trailing implement having a longitudinally extending frame pivotally supported on ground wheels and a ground engaging shovel connected at one end of the frame and movable with the frame vwith respect to the ground; a lifting mechanism adapted to be connected to the longitudinally extending frame and to the draw-bar of a tractor comprising, a draft frame including a longitudinally extending lifting member, a longitudinally extending draft beam positioned below the lifting member, non-parallel links pivotally connected to the draft beam and to the lifting member, a castering Wheel structure including a yoke extending transversely of the draft beam and pivotally connected thereto, castering wheels pivotally connected to the yoke in transversely spaced relation and adapted to support the draft beam Iwith respect to the ground, a draw-bar extension pivotally connected to the draft beam and adapted to connect to the drawbar of a tractor, adjustable means connected to the draft beam and to the lifting member for moving the beam and the member relatively apart thereby initially raising the lifting member with the draft beam supported on said castering wheel structure, and a lost-motion connection between said lifting member and said castering wheel structure whereby the castering wheel structure is raised upon the lifting of said draft frame to a predetermined height.

10. For a trailing implement having a longitudinally extending frame pivotally supported on ground wheels and a ground engaging shovel connected at one end of the frame and movable with the frame with respect to the ground; a lifting mechanism adapted to be connected to the longitudinally extending frame and to the draw-bar of a tractor comprising, a draft frame including a longitudinally extending lifting member, a longitudinally extending draft beam positioned below the lifting member, non-parallel links pivotally connected to the draft beam and to the lifting member, a castering wheel structure including a yoke extending transversely of the draft beam and pivotally connected thereto, castering wheels pivotally connected to the yoke in tra-ns- Versely spaced relation and adapted to support the draft beam with respect to the ground, a draw-bar extension pivotally connected to the draft beam and adapted to connect to the drawbar of a tractor, adjustable means connected to the draft beam and to the lifting member for moving the beam and the member relatively apart thereby initially raising the lifting member with' the draft beam supported on said castering wheel structure, a first link pivotally connected to said draft frame, and a second link pivotally connected to said first link and to said draw-bar extension, said links being pivotally movable upon movement of said draft frame whereby said second link engages the yoke of said castering wheel structure and raises said structure free of the ground.

LEWIS E. SMITH.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,888,504 Johnson et al Nov. 22, 1932 1,991,543 Cook Feb. 19, 1935 2,081,346 Altgelt May 25, 1937 2,146,898 Johnson Feb. v14, 1939 2,204,241 Young June 11, 1940 2,369,437 Court Feb. 13, 1945 2,410,918 Acton Nov. 12, 1946 

